Climate change will have adverse effects on global food production. Potential reduction in crop p... more Climate change will have adverse effects on global food production. Potential reduction in crop productivity will be one of the biggest challenges. The objective of this study was to assess the yield fluctuation using Agriculture Production Systems Simulator (APSIM), based on climate change predictions given by the Intergovernmental Panel on Climate Change (IPCC) in 2014. Rice (Oryza sativa L.) yields were simulated with increasing temperature, CO2 concentration and rainfall for three time periods; 2017 (current), 2050 and 2100. The simulations were run for medium (Bg359) and short (Bg300) duration rice varieties for 9 locations representing Wet Zone, Intermediate Zone and Dry Zone and for both Yala (March to September) and Maha (October to February) seasons. Simulation results revealed that the Wet Zone rice yield of Bg300 decreased in Maha season by 18% and 31% and the Dry Zone rice yield of Bg359 decreased in Yala season by 17%, and 42% for 2050 and 2100, respectively. Therefore, adaptation measures to overcome climate change-induced rice yield reduction in the future are essential to ensure the national food security.
This study assessed the climate resilience and characterized the existing farming systems in stee... more This study assessed the climate resilience and characterized the existing farming systems in steep terrain in the hilly regions in South Asia. The farming systems considered were at an elevation ≥300 m in the mountain regions of two sites from Sri Lanka (Hatton and Welimada) and one site each from Bangladesh (Chittagong) and Nepal (Jhikhu Khola). A Climate Resilience Index (CRIi) score, varying from 0 (negligible resilience) and 1 (very high resilience), was calculated for each household using 31 parameters under Adaptive Capacity (ADC), Absorptive Capacity (ABC) and Transformative Capacity (TC). To spatially represent the CRIi, the four study locations were mapped using Inverse Distance Weighted (IDW) interpolation technique of GIS. All 424 households in the study sites scored a CRIi between 0.36 and 0.76, while the average CRI was the highest in Hatton (0.67), followed by Welimada (0.60), Jhikhu Khola (0.59) and Chittagong (0.48). Different demographic, socioeconomic and environme...
A laboratory experiment was conducted to investigate the presence of phenolic acids in some anima... more A laboratory experiment was conducted to investigate the presence of phenolic acids in some animal-waste composts as well as their biological activity on the germination of sorghum (Sorghum bicolor Moench) seeds. Nine samples of composts, three in each group of cattle-, chicken-, and hog-waste composts, were extracted with deionized water at the rates of 10, 40, and 80 g L-L The seeds were imbibed in deionized water or respective compost extracts for 4 h. The content of water soluble phenolic acids in the compost extracts showed a negative correlation with the water uptake (r=-0.88"*), a-amylase activity (r=-0.82"*), and subsequent germination % (r-0.81'*) of sorghum seeds. The germination-inhibitory effects of the composts were observed in the acidic fraction of the compost extracts which contained the phenolic acids. The commercial phenolic acid preparations reduced the germination of sorghum seeds at a higher concentration (>50mg L-1) than the total phenolic acid content estimated in the composts. It was considered that the phenolic acids may be a major group of germination-inhibitory substances in animal-waste composts. The possibility of synergistic effects of phenolic acids in the germination-inhibitory composts was indicated. The presence of non-phenolic germination-inhibitors in the composts was also demonstrated.
Knowledge of population genetics and evolutionary history of wild progenitors of cultivated plant... more Knowledge of population genetics and evolutionary history of wild progenitors of cultivated plants is critical not only to understand the evolutionary processes leading to domestication, but also to their conservation and management (Doebley, Gaut, & Smith, 2006; Tanksley & McCouch, 1997). Studies on the level and distribution of genetic diversity in crops and their wild relatives will facilitate the effective utilization of the wild resources in crop genetic improvement and breeding (Tanksley & McCouch, 1997; McCouch et al., 2013). Given the fact that genetic diversity among commercial cultivars decreases substantially in the course of the domestication and breeding, scientists have taken great efforts to explore the genetic variability of wild species to meet the demands for crop breeding. They have particularly focused on the agronomically important traits such as grain yield, grain quality, and sufficient resistance to biotic or abiotic stress, for
ABSTRACT Effects of salinity on the isozyme activities of α-amylase in germinating sorghum seeds ... more ABSTRACT Effects of salinity on the isozyme activities of α-amylase in germinating sorghum seeds were studied under laboratory conditions. Seeds were imbibed in NaCl solutions at concentrations ranging from 0–500 nM (osmotic pressure: 0–2.28 MPa) for 0–24 h and the isozymes activities were estimated after disc-gel electrophoresis. Seed germination of sorghum was not affected by NaCl concentrations less than 100 nM (0.46 MPa). Germination was reduced by 50% at 300 nM NaCl (1.31 MPa), and completely inhibited at 500 nM (2.28 MPa). The α-amylase activity in the treated seeds followed a similar pattern to that of germination. At least five isozyme patterns of a-amylase were observed in germinating sorghum seeds. The activities of the respective isozymes were enhanced with increasing duration of imbibition in distilled water. When treated with 100 nM NaCl, the activities of isozymes 2 and 5 decreased, but this was compensated by the increased activity of isozyme 1. The sensitivity of isozymes to the salinity treatments varied where isozyme 1 was the most tolerant. The isozyme activities were completely inhibited by 500 nM NaCl. The results indicate that sorghum seeds could germinate well in saline environments up to 0.46 MPa. Higher osmotic pressure or saline concentrations could be detrimental to the seed germination of sorghum. The salinity tolerance could be attributable to the compensation of loss of activities of certain isozymes of α-amylase by the other types.
Http Dx Doi Org 10 1080 00380768 1992 10416959, Jan 4, 2012
Effect of animal-waste composts on a-amylase and protease activities of sorghum (Sorghum bicolor ... more Effect of animal-waste composts on a-amylase and protease activities of sorghum (Sorghum bicolor Moench) seeds was investigated under laboratory conditions using several cattle, chicken and hog-waste composts. The sorghum seeds were imbibed in 1, 4, and 8% (w/v) water extracts of the composts for 4 h. Alpha-amylase activity of the non-imbibed seeds increased by 46% during the 4-h imbibition in water. The increase of the amylase activity of the seeds imbibed in the majority of the germination-inhibitor composts, however, remained at a level between 50 and 66% of the increase observed in the water control. The amylase activity of the imbibed seeds showed a linear correlation with amount of water absorbed by the seeds (r=0.82"*) and also with the rate of subsequent seed germination (r=0.85"*). The protease activity was not affected by the addition of animal-waste composts. Starch degradation and the sugar and amino acid contents of the compost-imbibed seeds were in good agreement with the respective enzyme activities.
Evidence of research conducted on outreach activities of Faculties of Agriculture in the state Un... more Evidence of research conducted on outreach activities of Faculties of Agriculture in the state Universities of Sri Lanka focusing on agriculture related knowledge transfer is meagre or absent. Therefore, the objective of this study was to investigate, with an underlying theoretical framework, the factors that would predict the intention (participation decision) of academia to engage in outreach activities. The theory of planned behaviour (TPB) was applied for the prediction. A structured questionnaire was e-mailed and posted to randomly selected 67 % of the academic staff members from each of the eight Faculties of Agriculture (N = 257) in the state Universities of Sri Lanka, where 126 filled questionnaires (49 %) were returned after three reminders. The results indicated that the application of the theory along with additional variables could explain 39 % of the total variability. In general, satisfaction, recognition and rewards, subjective norms and positive attitudes towards outreach activities were the strongest predictors of intention to engage in outreach activities. Those who have engaged in outreach activities in the past with a higher general level of satisfaction are more likely to engage in outreach activities in future as well. These findings suggest that interventions to promote outreach activities of the academia of Faculties of Agriculture in the state Universities should target these factors in the short run together with establishment of an effective formal mechanism for outreach in the long run.
Long-chain fatty acids in germination-inhibiting animal-waste composts were identified by gas chr... more Long-chain fatty acids in germination-inhibiting animal-waste composts were identified by gas chromatography-mass spectrometry as myristic, palmitic, stearic, oleic, linoleic, and linolenic acids. These acids were found at concentrations greater than 0.25 mg (g dry compost)-1. The identified acids, together with lauric acid, and five kinds of short- and medium-chain fatty acid, were tested for their effects on the germination process of sorghum seeds. The authentic long-chain fatty acids, which were dissolved in a 1:9 (v/v) mixture of methanol and distilled water at 40 mg liter-1, significantly reduced the alpha-amylase activity, physiological water uptake, and ATP content of the germinating seeds during the first 24 h of inhibition, as well as the rate of germination of seeds. Among the tested fatty acids, myristic and palmitic acids were the most potent inhibitors of germination. The inhibitory effects of long-chain fatty acids were stronger than those of the phenolic acids. The s...
Page 1. Crop Diversification Strategies for Minor Irrigation Schemes Page 2. Crop Diversification... more Page 1. Crop Diversification Strategies for Minor Irrigation Schemes Page 2. Crop Diversification Strategies for Minor Irrigation Schemes Proceedings of the Workshop Organized i A the Irrigation Research Management Unit, . , . ...
ABSTRACT The spice export policy of Sri Lanka has focused on value addition, product and market d... more ABSTRACT The spice export policy of Sri Lanka has focused on value addition, product and market diversification and catering to the high-end markets to enhance foreign exchange earnings of the country. The overall objective of this study was to analyze export markets for Sri Lankan cinnamon (HS 090610, 090611, 090619 and 090620) (Cinnamomum varum Persl.), pepper (HS 090411 and 090412) (Piper nigrum L), cloves (HS 090700, 090710 and 090720) [Syzygium aromaticum (L) Merill & Perry] and nutmeg & mace (HS 090810, 090811, 090812, 090820, 090821 and 090822) (Myristica fragrans Houtt). The specific objectives are to (i) document the relative position of Sri Lanka among the other exporters, (ii) analyze the extent of export market diversification, and (iii) document tariff and non-tariff barriers imposed by major importing countries that reduce market access for the four spices. Trade data and tariff data from 2001 to 2011 were obtained from the International Trade Centre. Information on non-tariff barriers was extracted from the Food and Drug Administration of the U.S.A. Results of the analysis showed that Sri Lanka was within the top five exporters for cinnamon, cloves and nutmeg & mace occupying 36.8%, 4.6% and 8.0% of the global market, respectively, in 2011. However, global market share for Sri Lankan pepper in 2011 was 1.7% placing the country as 11 th . The top 10 importers of Sri Lankan spices occupy over 65% of the market share of which 85% is occupied by the top three importers for the four types of spices. India was the largest importer of Sri Lankan spices, contributing to 70% of pepper, 88.6% of cloves and 49% of nutmeg & mace exported (value basis) in 2011. For pepper, the number of markets, with more than 0.1% of share of total exported value, had increased from 2001 to 2011 whereas for cloves and nutmeg & mace there was a loss of 18% and 14% respectively. For cinnamon, Sri Lanka had no loss or gain of markets. Sri Lanka enjoys zero tariffs for spices except pepper, which is taxed at 70% by India. European Union and U.S.A provided premium prices for spices and impose a zero or lower tariff rates but spice exports from Sri Lanka to these markets were marginal. Sri Lankan black pepper has been detected to be of sub-standard quality due to the presence of Salmonella, which was 4.26% of total detentions of spices imported by U.S.A in December 2012. Non-compliance with the quality standards had shifted Sri Lanka to more regional markets like India where quality regulation was less stringent.
Climate change will have adverse effects on global food production. Potential reduction in crop p... more Climate change will have adverse effects on global food production. Potential reduction in crop productivity will be one of the biggest challenges. The objective of this study was to assess the yield fluctuation using Agriculture Production Systems Simulator (APSIM), based on climate change predictions given by the Intergovernmental Panel on Climate Change (IPCC) in 2014. Rice (Oryza sativa L.) yields were simulated with increasing temperature, CO2 concentration and rainfall for three time periods; 2017 (current), 2050 and 2100. The simulations were run for medium (Bg359) and short (Bg300) duration rice varieties for 9 locations representing Wet Zone, Intermediate Zone and Dry Zone and for both Yala (March to September) and Maha (October to February) seasons. Simulation results revealed that the Wet Zone rice yield of Bg300 decreased in Maha season by 18% and 31% and the Dry Zone rice yield of Bg359 decreased in Yala season by 17%, and 42% for 2050 and 2100, respectively. Therefore, adaptation measures to overcome climate change-induced rice yield reduction in the future are essential to ensure the national food security.
This study assessed the climate resilience and characterized the existing farming systems in stee... more This study assessed the climate resilience and characterized the existing farming systems in steep terrain in the hilly regions in South Asia. The farming systems considered were at an elevation ≥300 m in the mountain regions of two sites from Sri Lanka (Hatton and Welimada) and one site each from Bangladesh (Chittagong) and Nepal (Jhikhu Khola). A Climate Resilience Index (CRIi) score, varying from 0 (negligible resilience) and 1 (very high resilience), was calculated for each household using 31 parameters under Adaptive Capacity (ADC), Absorptive Capacity (ABC) and Transformative Capacity (TC). To spatially represent the CRIi, the four study locations were mapped using Inverse Distance Weighted (IDW) interpolation technique of GIS. All 424 households in the study sites scored a CRIi between 0.36 and 0.76, while the average CRI was the highest in Hatton (0.67), followed by Welimada (0.60), Jhikhu Khola (0.59) and Chittagong (0.48). Different demographic, socioeconomic and environme...
A laboratory experiment was conducted to investigate the presence of phenolic acids in some anima... more A laboratory experiment was conducted to investigate the presence of phenolic acids in some animal-waste composts as well as their biological activity on the germination of sorghum (Sorghum bicolor Moench) seeds. Nine samples of composts, three in each group of cattle-, chicken-, and hog-waste composts, were extracted with deionized water at the rates of 10, 40, and 80 g L-L The seeds were imbibed in deionized water or respective compost extracts for 4 h. The content of water soluble phenolic acids in the compost extracts showed a negative correlation with the water uptake (r=-0.88"*), a-amylase activity (r=-0.82"*), and subsequent germination % (r-0.81'*) of sorghum seeds. The germination-inhibitory effects of the composts were observed in the acidic fraction of the compost extracts which contained the phenolic acids. The commercial phenolic acid preparations reduced the germination of sorghum seeds at a higher concentration (>50mg L-1) than the total phenolic acid content estimated in the composts. It was considered that the phenolic acids may be a major group of germination-inhibitory substances in animal-waste composts. The possibility of synergistic effects of phenolic acids in the germination-inhibitory composts was indicated. The presence of non-phenolic germination-inhibitors in the composts was also demonstrated.
Knowledge of population genetics and evolutionary history of wild progenitors of cultivated plant... more Knowledge of population genetics and evolutionary history of wild progenitors of cultivated plants is critical not only to understand the evolutionary processes leading to domestication, but also to their conservation and management (Doebley, Gaut, & Smith, 2006; Tanksley & McCouch, 1997). Studies on the level and distribution of genetic diversity in crops and their wild relatives will facilitate the effective utilization of the wild resources in crop genetic improvement and breeding (Tanksley & McCouch, 1997; McCouch et al., 2013). Given the fact that genetic diversity among commercial cultivars decreases substantially in the course of the domestication and breeding, scientists have taken great efforts to explore the genetic variability of wild species to meet the demands for crop breeding. They have particularly focused on the agronomically important traits such as grain yield, grain quality, and sufficient resistance to biotic or abiotic stress, for
ABSTRACT Effects of salinity on the isozyme activities of α-amylase in germinating sorghum seeds ... more ABSTRACT Effects of salinity on the isozyme activities of α-amylase in germinating sorghum seeds were studied under laboratory conditions. Seeds were imbibed in NaCl solutions at concentrations ranging from 0–500 nM (osmotic pressure: 0–2.28 MPa) for 0–24 h and the isozymes activities were estimated after disc-gel electrophoresis. Seed germination of sorghum was not affected by NaCl concentrations less than 100 nM (0.46 MPa). Germination was reduced by 50% at 300 nM NaCl (1.31 MPa), and completely inhibited at 500 nM (2.28 MPa). The α-amylase activity in the treated seeds followed a similar pattern to that of germination. At least five isozyme patterns of a-amylase were observed in germinating sorghum seeds. The activities of the respective isozymes were enhanced with increasing duration of imbibition in distilled water. When treated with 100 nM NaCl, the activities of isozymes 2 and 5 decreased, but this was compensated by the increased activity of isozyme 1. The sensitivity of isozymes to the salinity treatments varied where isozyme 1 was the most tolerant. The isozyme activities were completely inhibited by 500 nM NaCl. The results indicate that sorghum seeds could germinate well in saline environments up to 0.46 MPa. Higher osmotic pressure or saline concentrations could be detrimental to the seed germination of sorghum. The salinity tolerance could be attributable to the compensation of loss of activities of certain isozymes of α-amylase by the other types.
Http Dx Doi Org 10 1080 00380768 1992 10416959, Jan 4, 2012
Effect of animal-waste composts on a-amylase and protease activities of sorghum (Sorghum bicolor ... more Effect of animal-waste composts on a-amylase and protease activities of sorghum (Sorghum bicolor Moench) seeds was investigated under laboratory conditions using several cattle, chicken and hog-waste composts. The sorghum seeds were imbibed in 1, 4, and 8% (w/v) water extracts of the composts for 4 h. Alpha-amylase activity of the non-imbibed seeds increased by 46% during the 4-h imbibition in water. The increase of the amylase activity of the seeds imbibed in the majority of the germination-inhibitor composts, however, remained at a level between 50 and 66% of the increase observed in the water control. The amylase activity of the imbibed seeds showed a linear correlation with amount of water absorbed by the seeds (r=0.82"*) and also with the rate of subsequent seed germination (r=0.85"*). The protease activity was not affected by the addition of animal-waste composts. Starch degradation and the sugar and amino acid contents of the compost-imbibed seeds were in good agreement with the respective enzyme activities.
Evidence of research conducted on outreach activities of Faculties of Agriculture in the state Un... more Evidence of research conducted on outreach activities of Faculties of Agriculture in the state Universities of Sri Lanka focusing on agriculture related knowledge transfer is meagre or absent. Therefore, the objective of this study was to investigate, with an underlying theoretical framework, the factors that would predict the intention (participation decision) of academia to engage in outreach activities. The theory of planned behaviour (TPB) was applied for the prediction. A structured questionnaire was e-mailed and posted to randomly selected 67 % of the academic staff members from each of the eight Faculties of Agriculture (N = 257) in the state Universities of Sri Lanka, where 126 filled questionnaires (49 %) were returned after three reminders. The results indicated that the application of the theory along with additional variables could explain 39 % of the total variability. In general, satisfaction, recognition and rewards, subjective norms and positive attitudes towards outreach activities were the strongest predictors of intention to engage in outreach activities. Those who have engaged in outreach activities in the past with a higher general level of satisfaction are more likely to engage in outreach activities in future as well. These findings suggest that interventions to promote outreach activities of the academia of Faculties of Agriculture in the state Universities should target these factors in the short run together with establishment of an effective formal mechanism for outreach in the long run.
Long-chain fatty acids in germination-inhibiting animal-waste composts were identified by gas chr... more Long-chain fatty acids in germination-inhibiting animal-waste composts were identified by gas chromatography-mass spectrometry as myristic, palmitic, stearic, oleic, linoleic, and linolenic acids. These acids were found at concentrations greater than 0.25 mg (g dry compost)-1. The identified acids, together with lauric acid, and five kinds of short- and medium-chain fatty acid, were tested for their effects on the germination process of sorghum seeds. The authentic long-chain fatty acids, which were dissolved in a 1:9 (v/v) mixture of methanol and distilled water at 40 mg liter-1, significantly reduced the alpha-amylase activity, physiological water uptake, and ATP content of the germinating seeds during the first 24 h of inhibition, as well as the rate of germination of seeds. Among the tested fatty acids, myristic and palmitic acids were the most potent inhibitors of germination. The inhibitory effects of long-chain fatty acids were stronger than those of the phenolic acids. The s...
Page 1. Crop Diversification Strategies for Minor Irrigation Schemes Page 2. Crop Diversification... more Page 1. Crop Diversification Strategies for Minor Irrigation Schemes Page 2. Crop Diversification Strategies for Minor Irrigation Schemes Proceedings of the Workshop Organized i A the Irrigation Research Management Unit, . , . ...
ABSTRACT The spice export policy of Sri Lanka has focused on value addition, product and market d... more ABSTRACT The spice export policy of Sri Lanka has focused on value addition, product and market diversification and catering to the high-end markets to enhance foreign exchange earnings of the country. The overall objective of this study was to analyze export markets for Sri Lankan cinnamon (HS 090610, 090611, 090619 and 090620) (Cinnamomum varum Persl.), pepper (HS 090411 and 090412) (Piper nigrum L), cloves (HS 090700, 090710 and 090720) [Syzygium aromaticum (L) Merill & Perry] and nutmeg & mace (HS 090810, 090811, 090812, 090820, 090821 and 090822) (Myristica fragrans Houtt). The specific objectives are to (i) document the relative position of Sri Lanka among the other exporters, (ii) analyze the extent of export market diversification, and (iii) document tariff and non-tariff barriers imposed by major importing countries that reduce market access for the four spices. Trade data and tariff data from 2001 to 2011 were obtained from the International Trade Centre. Information on non-tariff barriers was extracted from the Food and Drug Administration of the U.S.A. Results of the analysis showed that Sri Lanka was within the top five exporters for cinnamon, cloves and nutmeg & mace occupying 36.8%, 4.6% and 8.0% of the global market, respectively, in 2011. However, global market share for Sri Lankan pepper in 2011 was 1.7% placing the country as 11 th . The top 10 importers of Sri Lankan spices occupy over 65% of the market share of which 85% is occupied by the top three importers for the four types of spices. India was the largest importer of Sri Lankan spices, contributing to 70% of pepper, 88.6% of cloves and 49% of nutmeg & mace exported (value basis) in 2011. For pepper, the number of markets, with more than 0.1% of share of total exported value, had increased from 2001 to 2011 whereas for cloves and nutmeg & mace there was a loss of 18% and 14% respectively. For cinnamon, Sri Lanka had no loss or gain of markets. Sri Lanka enjoys zero tariffs for spices except pepper, which is taxed at 70% by India. European Union and U.S.A provided premium prices for spices and impose a zero or lower tariff rates but spice exports from Sri Lanka to these markets were marginal. Sri Lankan black pepper has been detected to be of sub-standard quality due to the presence of Salmonella, which was 4.26% of total detentions of spices imported by U.S.A in December 2012. Non-compliance with the quality standards had shifted Sri Lanka to more regional markets like India where quality regulation was less stringent.
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